my favourite hammer, which was sold as a repousse hammer is now
falling apart. The next time I use it, the head will probably fly
across the room! I need to save up for some decent hammers or learn
to make/repair tools.

Helen, you can fix it. Add an extra wedge in the end wood, or drive
a screw into the space and cut it off. I hear that you can soak the
head in antifreeze to make it swell permanently. Dry winter air can
be hard on hammer-handle fit, but it is by no means the end of your
favorite hammer!

For example, my favourite hammer, which was sold as a repousse
hammer is now falling apart. The next time I use it, the head will
probably fly across the room!

Yes, Helen, tools mostly don’t last forever, even good ones if they
are used. Hammers: you can buy hammer handles lots of places -
hardware stores and jewelry supply. You can also buy wedges, which
are what you put into the split where the handle goes into the head -
bang it in and then trim it off. A good hammer that’s just a bit
loose can often be tightened up, though it may come loose again in
time. Hold the handle perpendicular, hammer head up, and pound the
base of it on something hard - anvil, floor, bench, several times
very strongly and sharply. The inertia of the head will drive it back
onto the handle…

If the head is loose, turn the hammer upside down, smack it a couple
of good whacks with another hammer, piece of 2x4, and the head will
tighten, If there is a wedge in the wood on top, drive that down
further after whacking.

next time the head is off the handle go get some J B weld from the
auto parts store or hardware store follow the directions and apply
the mixed epoxy to the head socket and handle wait 24 hours and you
wont have any more hammers coming apart - goo

I have a blacksmithing background… I’m used to swinging a hammer
pretty hard and fast, and heads loosen fairly quickly.

My opinion is, don’t shortcut the fix. Your hammers FEEL better when
they are firmly and solidly mounted on the handle. If it’s your
favorite hammer, treat it like the jewel that it is!

I replace handles rather than try to keep adding wedges, nails,
tapping the head further down, dipping in antifreeze, etc… those
fixes only last a little while and to me it’s worth the time and
aggravation of fitting a brand new handle for the wonderful feel in
hand that results!

Take the hammer and measure the opening for the handle on both sides.
In good hammers the opening will be conical, one measurement will be
larger.

If both measurement are the same, do not bother with anything, just
throw the thing away.

If one measurement is larger, make sure that hammer goes on the
handle with larger opening first.

After that the John’s method will work perfectly. It goes without
saying that your new handle should have the same conical profile.
Secure it with the wedge and you should have no trouble for many
years
to come.

I replace handles rather than try to keep adding wedges, nails,
tapping the head further down, dipping in antifreeze, etc... those
fixes only last a little while and to me it's worth the time and
aggravation of fitting a brand new handle for the wonderful feel
in hand that results!

Definitely worth a try. Although I’m considering in investing in
some decent hammers as all my hammers were inexpensive or just plain
cheap so I could get started. I’m slowly replacing cheap and broken
tools as I go along.

Here are a few things that you to help tighten a loosened hammer
head on a handle:

Place the head on the handle. Holding the handle vertically with
the hammer head at the top, place the end of the handle on a firm
surface, and bang it down on the surface. This should drive the
hammer head onto the handle securely.

Next, if the head still seems a little loose, put one drop of the
liquid that is used to tighten chair rungs on the part of the handle
that shows through the hammer head. This material causes wood to
swell; it is NOT Glue. There are two brands that I’m aware of:
Chair-Loc and Bondex Wood Swell & Lock. USE ONLY ONE DROP. If you
use too much, that part of the handle will swell too much and the
wood might split the hammer head or the handle might weaken at that
point. You might have to apply this material once or twice a year.

You can also use a small wedge, even a slim rectangle of steel or
brass sheet will do, hammered into the end of the handle that shows
through the hammer head, to help spread that end of the handle and
hold the head on firmly.

My first career was as a carpenter until a three story fall ended
that career. So I know a bit about hammer handles and how to replace
them without the coming loose. First when putting the handle in the
hammer once it is started in the hole, hold the handle hammer head
down not touching anything and smack the end of the handle with a
hammer or big rawhide or wood mallet. Keep hitting it until the
hammer head is seated tight against the taper of the handle. This
gets the hammer head seated properly. Now, apply a dab of water
based wood glue to the wooden wedge and pound it into the split of
the handle supporting the bottom of the handle on something solid.
Waterbased wood glue is important because it will swell the wood
tight. Cut off the top of the wedge flush with the top of the handle.
If there are steel wedge(s) supplied with the handle drive them in at
45 degrees looking at the top of the hammer. Now coat the wood
exposed on the top of the hammer handle with some sort of sealer. We
used to use fingernail polish (yeah I know a bunch of rough tough
carpenters having finger nail polish seems kinda weird). Don’t used
the hammer for 24 hours so the glue has a chance to dry.

Hitting the hammer handle on the end while holding the handle is
also a good way to tighten loose hammer handles.

I have a blacksmithing background... I'm used to swinging a hammer
pretty hard and fast, and heads loosen fairly quickly.

Yes, Kevin puts it well. In Helen’s case, I assume she can get by
with tightening it up occasionally, at least until it becomes urgent
for her. But there have been posts about putting screws in the head
and various things - yes, they can work, and they can also not work.
As Leonid points out, if the hammer head isn’t tapered in the hole,
it’s junk anyway. As Kevin says, though, do you really want to work
with a hammer that has screws and nails stuck in it? You might, and
it might fix the problem, yes. I prefer to use tools that make me
feel like they are stong, together and properly made, though, and in
the long run you’re better off just doing it properly, if it sees any
use. Get a new handle and a proper wedge, shape it so the head just
squeezes on, put some epoxy if you like, pound it on (don’t hit the
head, pound the butt on the floor), put in the wedge (epoxy, if you
like), pound that in as tight as possible, and then cut off the
excess and sand it down - THAT’S a hammer…Or for a $10 hammer
just get another one…

The shape of the handle is important. Consider the shape and size of
a chasing hammer handle and the bigger stiffer straighter handle on
a metalsmithing forging hammer let alone putting a blacksmithing
hammer handle into the confusion. If you are replacing handles, pay
attention. Buying the good hammers instead of general use hammers
from hardware stores or flea markets gives you a hammer head that
balances with the handle for the purpose you want it to serve.
(Typing hammer handles over and over made me think I was doing
tongue twisters.)